package sword;

/**
 * @Author: 海琳琦
 * @Date: 2022/6/6 10:51
 * https://leetcode.cn/problems/qing-wa-tiao-tai-jie-wen-ti-lcof/
 */
public class Title10II {

    /**
     * dp[i]：表示跳到第i级楼梯的跳法
     * 递推公式 dp[i] = dp[i-1] + dp[i-2]
     * @param n
     * @return
     */
    public int numWays(int n) {
        if (n == 0 || n == 1) {
            return 1;
        }
        int[] dp = new int[n + 1];
        dp[0] = 1;
        dp[1] = 1;
        for (int i = 2; i <= n; i++) {
            dp[i] = (dp[i - 1] + dp[i - 2]) % 1000000007;
        }
        return dp[n];
    }

    public static void main(String[] args) {

    }
}
